Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stroke impairs learning also in remote brain regions; first success with new therapeutic approach

25.08.2011
Stroke patients often have difficulties with re-learning simple skills such as walking or talking, and the causes are still unknown.

In a new study, researchers from the Bernstein Network and the Universities of Göttingen and Jena now show that a stroke even affects the learning ability of remote brain areas. Learning processes in the visual system of mice were impaired, in some cases even for weeks. The scientists conclude that plastic brain changes are modulated by networks far bigger than previously assumed. By administration of anti-inflammatory drugs, some of the networks were able to regain their learning ability.

In Germany alone, every year some 200,000 people suffer from strokes. It is still not understood why the affected subjects often find it so difficult to relearn everyday abilities. There are still debates about the best starting time for therapy and the best approach towards medication. Scientists have long observed that the localized blood flow disturbance can also affect distant brain areas. Now scientists led by Professor Siegrid Löwel and Professor Otto Witte have examined the effects of a local stroke on neuronal plasticity in the visual system of mice as part of the “Visual Learning” project of the Bernstein Focus: Neuronal Basis of Learning.

Closing one eye in healthy animals leads to an increase in the visual acuity of the remaining eye, and both hemispheres process information from the open eye more intensely. “We have shown that the brain loses this ability after a stroke,” says Franziska Greifzu, PhD student in the laboratory of Prof. Siegrid Löwel, a neurobiologist at the Bernstein Focus Neurotechnology and the University of Göttingen, and head of the study. For the investigation, a stroke was induced in an area of the cerebral cortex that has no known effect on the visual system. Closing one eye immediately after the stroke resulted in the mouse brain being unable to normally adapt to the new situation; it had lost its ability to learn. Two weeks after the brain damage, the ability to adapt was partly regenerated.

The researchers examined whether inflammation could be responsible for this compromised learning. Therefore, they treated the animals immediately after the stroke with an anti-inflammatory drug. The result was that the treated animals developed, as with healthy animals, an increased visual acuity of the open eye. “The impaired learning ability after a stroke could be rescued to normal levels by use of anti-inflammatory drugs”, explains Witte, a neurologist at the University Hospital of Jena.

How the damaged area of the brain affects the visual system is still unclear. “There are obviously a lot more interactions between brain areas than we know and usually test experimentally,” says Löwel. Now the scientists want to examine more closely what changes a stroke entails on the cellular level and how learning ability can be completely restored. The results were published in the renowned scientific journal PNAS.

The project “Visual Learning” of the Bernstein Focus: Neuronal Basis of Learning is part of the Bernstein Network Computational Neuroscience (NNCN) in Germany. The NNCN was established by the German Federal Ministry of Education and Research with the aim of structurally interconnecting and developing German capacities in the new scientific discipline of computational neuroscience. The network is named after the German physiologist Julius Bernstein (1835–1917).

Original publication:
Greifzu et al. (2011): Global impairment and therapeutic restoration of visual plasticity mechanisms after a localized cortical stroke. PNAS, published ahead of print August 24, 2011, doi:10.1073/pnas.1016458108.
For further information please contact:
Prof. Dr. Siegrid Löwel
sloewel@gwdg.de
Systems Neuroscience Group
Bernstein Focus: Neurotechnology (BFNT) and
J.F. Blumenbach Institute of Zoology and Anthropology
Göttingen University
Von-Siebold-Str. 4
37073 Göttingen
Germany
Phone +49 (0) 551 3920161/60

Johannes Faber | idw
Further information:
http://www.nncn.de/
http://www.uni-goettingen.de/
http://www.uni-jena.de/

More articles from Studies and Analyses:

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>